Device for forming closing heads at rivets

ABSTRACT

A device or apparatus for forming closing heads at rivets with the aid of a rivet set or anvil performing substantially looplike revolving movements. According to the invention at least two drive members serve to drive the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted.

I United States Patent 1 3,653,243 Ramseier [451 Apr. 4, 1972 54 DEVICE FOR FORMING CLOSING UNITED STATES PATENTS HEADS AT RIVETS 3,440,850 4/1969 Friedrich ..72/429 x 2 Inventor; Paul Ramsei", pf ffik Switzerland 3,173,281 3/1965 Bodmer ..72/67 2,998,839 9/1961 Ingwer .72/l26 X [73] A ign Bm r A f ffi n, Switzerland 3,117,617 l/l964 Meese ..72/ 126 x [22] Filed: Apr. 3, 1970 Primary Examiner-J. Spencer Overholser 211 App! 25 514 Assistant Examiner-John E. Roethel Attorney-Werner W. Kleeman [30] Foreign Application Priority Data [5 7] ABSTRACT Apr. 1 1, 1969 Switzerland ..5502/69 A device 0! apparatus for forming closing heads at rivets with the aid of a rivet set or anvil performing substantially loop-like [52] CL" 72/122 72/l26 revolving movements. According to the invention at least two [51] Int Cl Bzld 3/02 1b 3/06 drive members serve to drive the rivet set, the movements of 58 d i "72/112 d 122 126 which are superimposed and wherein at least one such movele o are memcanbeadjusted [56] References Cited 10 Claims, 6 Drawing Figures PATENTEDAPR 4 1972 SHEET 1 BF 2 2 m m w 7/ 7///////// 4/9 r //////J -f Fig. 1

ATTORNEY INVENTOR ATTORNEY in/A fl mse/sle SHEET 2 OF 2 Fig. 5

PATENTEDAPR 4 I972 DEVICE FOR FORMING CLOSING HEADS AT RIVETS BACKGROUND OF THE INVENTION The present invention relates to a new and improved device for forming closing heads at rivets with the aid of a rivet set or anvil which carries out substantially loop-like revolving movements.

Riveting machines are known to the art wherein the rivet set support means thereof traces a hypocycloidal-like path, this movement being generated by hypocycloidal gearing. The movement of the rivet set is fixed by the preselected gear teeth ratio and cannot be changed. Yet, in practice it has been found that such a drive, while satisfactory for predetermined riveting operations, on the other hand is not completely satisfactory when working different rivet diameters and different rivet materials.

During the forming of rivet heads manufactured from different rivet materials, typically for instance steel, brass, copper, light metals, these materials behave quite differently during the formation of the closing head in that the displacement of material must proceed differently depending upon the hardness of such material if there is to be achieved an optimum mode of operation. In the prior art devices employing a fixed hypocycloidal gearing drive mechanism, the radial movement of the rivet set exceeds the tangential movement by about 50 percent. However, it has been determined that especially when riveting hardened or casehardened rivets it is advantageous if the radial movement exceeds the tangential movement considerably more than such was the case with the known devices.

Furthennore, practical experience has shown that with increasing forming of the closing head there occurs a hardening of the material so that, for this reason, it is advantageous if with progressive formation of the closing head the course of movement of the rivet set is varied in the sense that the radial movement considerably supersedes the tangential movement.

SUMMARY OF THE INVENTION Accordingly, it is a primary objective of the present invention to provide an improved apparatus for the forming of closing heads at rivets which effectively overcomes the aforementioned drawbacks of the prior art constructions.

Another more specific object of the present invention relates to an improved apparatus for forming closing heads at rivets which allows for the desirable movement of the rivet set just described above.

Still a further significant object of the present invention relates to an improved apparatus of the mentioned type which enables changing the path of movement carried out by the rivet set.

Now, in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the inventive apparatus is generally manifested by the features that the rivet set is driven by at least two drive members, the movements of which are superimposed and wherein at least one such movement can be regulated or adjusted.

By virtue of the aforementioned construction, it is possible to effectively accommodate the movements carried out by the rivet set in each case exactly to the existing conditions both with regard to material as well as the magnitude of the forming operation or the state or progression thereof.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood and objects other than those set forth above, will become apparent, when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:

FIG. 1 is a longitudinal sectional view through a first embodiment of inventive apparatus for forming closing heads at rivets;

FIG. 2 is a modified version of the inventive apparatus, in longitudinal sectional view, employing an eccentric and slide arrangement;

FIG. 3 is a front view of the embodiment depicted in FIG. 2, viewed in the direction of the arrow A;

FIG. 4 is a further embodiment of inventive apparatus taken in longitudinal section;

FIG. 5 is a front view of the embodiment depicted in FIG. 4, taken in the direction of the arrow D; and

FIG. 6 is another embodiment of apparatus of the invention utilizing partially hydraulically controlled movements.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Describing now the drawings, in the exemplary embodiment of inventive apparatus for forming closing heads at rivets as shown in FIG. 1, there will be seen a main spindle l which is guided to be axially displaceable but non-rotatable at a suitable non-illustrated machine head. The main spindle l is provided with a drive element here in the form of a rotatable spin dle 2 which is guided in a longitudinal bore of the main spindle 1, as shown. A further drive element or member 3 is arranged internally of the rotatable spindle 2 in coaxial arrangement. This drive element 3 is in operable driving association with an eccentric portion 4. The eccentric portion or member 4 is rotatably located in a lower bore portion which extends eccentrically with respect to the bore 12. Further, the driving connection between the drive element 3 and the eccentric element 4 is achieved by the use of a suitable flexible connection member 5 which can laterally deflect in accordance with the eccentric revolving movement of the eccentric portion or element 4.

Continuing, it will be understood that the rivet set or anvil 6 is inserted into a tool holder 7. The upper surface of this tool holder 7 is constructed as a sector of a sphere and with the aid of a spring member 9 is pressed against a ball socket 8 located internally of the main spindle 1. An eccentric pin member 10 depends downwardly from the eccentric portion 4. A drive ball or element 18 is seated upon the eccentric pin member 10, drive ball 18 engaging into an opening of the rivet set sup port 7, as shown. In the extreme position the axes of the eccentric pin member 10 and the drive element 3 are offset with respect to one another through the distance 2, as shown in FIG. 1. During rotation of the eccentric pin member 10 which is rigidly connected with the eccentric element 4 the rivet set support 7 thus carries out a wobbling movement, whereby the rivet set axis intersects the rivet axis. If additionally the other drive element i.e., spindle member 2 is driven in the same rotational sense with a different number of revolutions or in the opposite rotational sense, then both movements will be superimposed and the middle point of the eccentric pin or bolt member 10 carries out a loop'shaped, rosette-like movement. Depending upon the relationship of both velocities or speeds to one another, it is possible in this manner to produce quite different loop shapes or configurations. Consequently, the most advantageous movement for forming the closing head of the rivet 11 can be optimumly accommodated to the existing conditions.

FIGS. 2 and 3 depict a variant construction of the inventive apparatus in which a drive spindle 2 and an additional drive spindle 13 are likewise driven with a differential speed of rotation or different velocities. Also in this case the spindle member 2 is mounted in a main spindle, just as was the case with the initially described embodiment of FIG. 1. The eccentric pin or bolt member 15 at the lower end of the additional spindle 13 engages with a slide or carriage 16 which, in turn, supports an eccentric pin 10. The slide 16 is supported for linear displacement in a guide groove 17. Now if the drive spindle member 12 and the additional drive spindle l3 rotate, in this embodiment there occurs depending upon the difference of the speed of rotation between both drives a somewhat different type of loop movement than with the apparatus structure of FIG. 1. But the mode of operation is analogous.

Now in the embodiments depicted in FIGS. 4 and 5 there are likewise provided two drive mechanisms. The one drive element 21 is constructed as a rotatable disc member which is provided with an eccentric opening 26 or an opening 26 which deviates from the circular shape, and which serves as a templet for the movement of a double-arm lever member 22. This lever member 22 is pivotably mounted about the axis 23 approximately at the central region of the spindle member 2 by means of a transversely extending bolt or pivot pin 24. A

pin or bolt member 25 is located at the lower end of the lever member 22, pin 25 corresponding to the eccentric pin of the other embodiments heretofore described and which serves to engage with the rivet set support means 7. Now if the drive element 21 and the drive spindle member 2 are placed into rotation, with the number of revolutions being difierent, then this pin member 25 again carries out the desired composite motion.

In the arrangement shown in FIG. 6 there is disclosed an embodiment of invention in which the one drive occurs hydraulically. Here a drive spindle member 34 is placed into rotation by the schematically depicted motor 50. The lower end of spindle member 34 is equipped with a linearly movable carriage or slide member 31 which, in turn, carries the pin or bolt member 10. Bolt or pin member 10 just as with the other embodiments heretofore described serves to engage with the rivet set support means 7. Continuing, it will be observed that at the upper end of the spindle 34 connection conduits 35 and 37 are coupled with a collar member 36 and serve for the infeed and withdrawal of a pressurized fluid medium. This pressurized fluid medium is guided through a piston member 38 by means of longitudinal bores provided internally of the spindle member 34. As a result, the piston member 38 moves the drive carriage or slide 31 back and forth. By controlling the fluid medium, it is possible to vary the stroke velocity and therefore the number of strokes per unit of time of the carriage or slide 31. Also in this arrangement there occurs a total movement of the rivet set 7 which is composed of the rotational movement of the drive spindle member 34 and the toand fro movement of the drive carriage or slide 31 and, just as with the other embodiments, it is possible to undertake the forming or setting of the closing heads of the rivets.

The spindles 2 and 34 are each driven, preferably with a constant number of revolutions, by a respective electric motor, such as drive motor 50 of FIG. 6, whereas the second drive member 3, 13, 21 is driven with a variable number of revolutions, and for instance with the hydraulic arrangement of FIG. 6 the carriage or slide 31 is moved with varying number of strokes.

While there is shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.

What is claimed is:

I. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted independently of the other such movement in order to selectively vary the configuration of such loop-like revolving movements.

2. The apparatus as defined in claim 1, wherein said drive element means incorporate mechanism for causing both drive element means to perform a rotational movement with different number of revolutions.

3. The apparatus as defined in claim 2, further including a ball socket, a rivet set support bearing against said ball socket,

one of said drive element means embodying a hollow spindle member, a revolving eccentric bolt member portion equipped with an eccentric pin member disposed internallypf said hollow spindle member at the lower end thereof, said eccentric pin member engaging with said support of the rivet set.

4. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted, said drive element means incorporating mechanism for causing both drive element means to perform a rotational movement with different number of revolutions, one of said drive element means comprising a drive spindle provided with a bore, a drive shaft coaxially mounted in said bore of said drive spindle, an eccentrically mounted bolt member disposed in said bore, and a flexible connection element for operably coupling said drive shaft with said eccentrically mounted bolt member.

5. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted, a rivet set support, one of said drive element means encompassing a shaft member having a lower end provided with an eccentric pin, a linearly guided slide member, said eccentric pin engaging with said linearly guided slide member, a projection provided for said linearly guided slide member which extends into said rivet set support.

6. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted, a rivet set support, and wherein one of said drive element means comprises a hollow drive spindle, the other of said drive element means comprises a double-arm lever member mounted for pivotable movement about a transverse extending axis within said hollow drive spindle, said double-arm lever member having an upper end and a lower end, rotatable template means cooperating with said upper end of said doublearm lever member, projection means provided at the lower end of said double-arm lever member and engageable with said rivet set support.

7. The apparatus as defined in claim 6, wherein said template means is provided with an eccentric opening.

8. The apparatus as defined in claim 6, wherein said template means is provided with an opening which deviates from a circular configuration.

9. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted, a rivet set support, one of said drive element means comprising a drive spindle member, the other of said drive element means comprising a hydraulically actuated reciprocating piston member cooperating with said drive spindle member, a linearly guided slide member driven by said piston member, said linearly guided slide member being equipped with projection means for engaging with said rivet set support.

10. The apparatus as defined in claim 1, wherein one of said drive element means comprises an external drive spindle member and the other drive element means comprises mechanism arranged internally of said external drive spindle member, and means for driving said external drive spindle member with a constant number of revolutions and the internal drive mechanism with a variable number of revolutions. 

1. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movemEnts of which are superimposed and wherein at least one such movement can be adjusted independently of the other such movement in order to selectively vary the configuration of such loop-like revolving movements.
 2. The apparatus as defined in claim 1, wherein said drive element means incorporate mechanism for causing both drive element means to perform a rotational movement with different number of revolutions.
 3. The apparatus as defined in claim 2, further including a ball socket, a rivet set support bearing against said ball socket, one of said drive element means embodying a hollow spindle member, a revolving eccentric bolt member portion equipped with an eccentric pin member disposed internally of said hollow spindle member at the lower end thereof, said eccentric pin member engaging with said support of the rivet set.
 4. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted, said drive element means incorporating mechanism for causing both drive element means to perform a rotational movement with different number of revolutions, one of said drive element means comprising a drive spindle provided with a bore, a drive shaft coaxially mounted in said bore of said drive spindle, an eccentrically mounted bolt member disposed in said bore, and a flexible connection element for operably coupling said drive shaft with said eccentrically mounted bolt member.
 5. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted, a rivet set support, one of said drive element means encompassing a shaft member having a lower end provided with an eccentric pin, a linearly guided slide member, said eccentric pin engaging with said linearly guided slide member, a projection provided for said linearly guided slide member which extends into said rivet set support.
 6. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted, a rivet set support, and wherein one of said drive element means comprises a hollow drive spindle, the other of said drive element means comprises a double-arm lever member mounted for pivotable movement about a transverse extending axis within said hollow drive spindle, said double-arm lever member having an upper end and a lower end, rotatable template means cooperating with said upper end of said double-arm lever member, projection means provided at the lower end of said double-arm lever member and engageable with said rivet set support.
 7. The apparatus as defined in claim 6, wherein said template means is provided with an eccentric opening.
 8. The apparatus as defined in claim 6, wherein said template means is provided with an opening which deviates from a circular configuration.
 9. An apparatus for forming closing heads at rivets with the aid of a rivet set performing substantially loop-like revolving movements, comprising at least two drive element means for driving the rivet set, the movements of which are superimposed and wherein at least one such movement can be adjusted, a rivet set support, one of said drive element means comprising a drive spindle member, the other of said drive element means comprising a hydraulically actuated reciprocating piston member cooperating with said drive spindle member, a linearly guided slide member driven by said piston member, said linearly guided slide member being equipped witH projection means for engaging with said rivet set support.
 10. The apparatus as defined in claim 1, wherein one of said drive element means comprises an external drive spindle member and the other drive element means comprises mechanism arranged internally of said external drive spindle member, and means for driving said external drive spindle member with a constant number of revolutions and the internal drive mechanism with a variable number of revolutions. 